Pipe covering



Sept. 13, 1932. W` R; @REIG 1,876,665

PIPE COVERING Filed June 29, 1929 Figi INVENTOR WILL/HM B 62E/G l B'Y Hls ATTQRNEY Patented Sept. 1,3, 1932 l' UNITED YSTATES i PATENT ol-"Flcsv WILLIAM R. GREIG, OF BERKELEY, CALIFORNIA, ASSIGNOR TO THE FARAFFINE COM- PNIES, INC., OF SAN FRANCISCO, CALIFORNIA, A CORPORATION OF DELAWARE PIPE COVERING Application mea June 29, 1929. serial No. 374,710.

. .Y My invention relates to coverings for protectingpipes from the corrosive action due to ground water with its dissolved salts, electrolysis, and the like.

The preferred material for suchV covering is fabric, such, for example, as a rag felt,

which is saturated with water resistant material, usually of a bitummous character.

The value of such coverings depends largely .w upon complete continuity,

lauthat the covering may be broken.

It is one of the objects of my invention,

therefore, to provide a covering which will be highly resistant to abrasion.

Another object of my invention is to pro.

2o vide a pipe covering which may be applied as readily as the ordinary abrasion sensitive type. l s Yet another object of my invention is to provide a pipe covering having -a light-refleeting surface, which will prevent the pipes,

lying in the sun before being laid, from rising to a temperature so high as to make their handling diiiicult, and to cause running or oozing of the water resistant material.

Still another object of my invent-ion is to provide an abrasion resistant pipe covering in which the abrasion resistant surface does not itself offer a point of ingress for the fluids which cause corrosion.

A further object vof my invention is to provide a covering of the character described which'y is itself of moderate cost, and which may be applied with no greater expense than that involved in the use of coverings of the ordinary type.

f My invention possesses other objects and valuable features, some of which will be set forth in the following description of my invention which is illustrated in the` drawing forming part of the specification. It is to be understood that I do -not limit myself to the showing made by the said description and drawing, as I may adopt varying forms of my invention within Vthe scope of the claims.

Referring to the drawing:

Figure 1 depicts the covering'of my invention as applied to a section of pipe.

Figure 2 is a view similar to Figure 1, and showing my invention in a modified form.

Figure 3 is-a detailed sectional view showing the lap joint usedin the preferred form of my invention.

Broadly considered, the pipe covering of my invention comprises a. sheetl or strip of fabric which is impregnated with a water resistant material, and to the outer surface of which is cemented a sheet of abrasion resisting material, such as a tough, dense paper. The coverng material is preferably formed in rolls, from which it may be applied spirally to the pipe, either by hand or by a machine.

Describing a preferred embodiment of my invention in greater detail, the reference character 6 indcates a sheet of fabric which may be a woven material such as a cotton or burlap sheeting, but is preferably a felted material such as isused as a base for sheet roofing. There is a wide choice of such materials,'including asbestos and other mineral felts, but the so-calledrag felt is low in price and quite satisfactory for the purpose. The fabric sheet is impregnated or saturated with a water resistant material. The saturants may also be widely varied; asphalt, stearine pitch, coal or pine tar, and various gums and oils, either alone or in combination, being suitable. The preferred material is an asphalt having 4a softening point of approximately 110 Fahrenheit, and a penetration of approximately Q00 at 77l Fahrenheit, 10() grams, 5 seconds, by the methods of the American Society for Testing Materials, standards of 1927. If a woven fabric is used, the saturant should be harder, -and should Vfill the interstices between the meshes completely.

Secured tothe fabric 6 by a layer of cement 7 is a sheet 8 of abrasion resistant material.

A suitable cement is anasphaltwhich is penetration of 20 at 77 F., 100 grams,l5 sec- A. S. T. M., standards of 1927, having onds,

Y The been found satisfactory in practice.

cement is preferably applied to the felt as a.v

coating, the under side of-the fabric being coated or uncoated, as may be preferred from manufacturing considerations.

A suitableabrasion resisting material is a l tough kraft paper, which is preferably unsaturated and applied to the strip offabric as a narrower strip, one edge of which coincides with that of the fabric, thus leaving la kportion of the other edge exposed to form a lap surface 9, as best shown in Figure 3.

Besides its abrasion resistant function, the

' f paper, by virtue of its light-reflecting surface,

serves to limit the temperature to which the A.covered pipe will rise when stored in the sun, and so, not only make its handling easier, but

also prevent running or oozing of the saturant.

erably made into rolls,

The covering formed as described is preffrom which it may conveniently be applied to the pipe..

This may be done either by hand or by machine. However the application is made, the pipe is preferably first prepared with a. priming'coat of asphaltic paint 12, covered by a point of 145 F., and a penetration between 30 and 40, at 77 F., 100 grams, 5 seconds, A. S. ZT. M., standards of 1927 This same ma- .terial mixed with equal parts of gilsonite andcut with gasoline to a brushing cons istenc-y, may alsol be used for the priming 'coat o'f paint.

The covering is wrapped spirallyabout the pipe, each turn ofthe covering lapping over thefexposed portion of the felt so that the entire outer surface of the pipe is covered 'with' paper. Since the paper does not ex- Y .tend'materially into the lap joint, there is no 'tendency for it to conduct moisture by capillarity to a point where it could reach the plpe.

member, and a wrapping on sai pipe comprising a sheet of fabric saturated with a waterproof'material and a sheet of abrasion resistant material cemented thereto so as to leave an edge of said fabric exposed, said wrapping being lapped to cover the exposed edge of the fabric.

In testimony whereof, I have hereunto set my hand.

WILLIAM R. GREIG.

f layer of cement 13. A satisfactory material -for the latter is an asphalt with a softening There the pipe is to be used in conditions 45 "of unusual severityv as to temperature, con-V centration of salt, or strong electric ground current, the protective coating may be applied over an inner wrapping of felt 14, -as is shown in Figure 2. In this case, of course., only the outer'wrapping need be protected by the abrasion resisting covering.

Where the risein temperature of the pipe, due to absorbed radiation, need not be considered, the paper coatingl may besaturated with a material ofthe same character as is used on the felt. In this case, both the paper and the felt may be of the same width, since the saturated paper 4will not conduct moisture. ure 2.

Kraft paper, also knownas Swedish manila or express paper, is the preferred material for the abrasion resistant layer, because of its tough, dense character and low This construction 'is also shown in Figcost. -Other papers may, of course, be sub- 'stituted, as, for example, sulphite papersf` 

